package com.fit;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
/**
* Servlet implementation class CheckCode
*/
public class CheckCode extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public CheckCode() {
super();
// TODO Auto-generated constructor stub
}
private Color getRandColor(int s, int e) {
Random random = new Random();
if (s > 255)
s = 255;
if (e > 255)
e = 255;
int r = random.nextInt(e - s) + s; // 隨機生成RGB中的R值
int g = random.nextInt(e - s) + s; // 隨機生成RGB中的G值
int b = random.nextInt(e - s) + s; // 隨機生成RGB中的B值
return new Color(r, g, b);
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
this.doPost(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setHeader("Pragma", "No-cache");
response.setHeader("Cache-Control", "No-cache");
response.setDateHeader("Expires", 0);
//指定生成的響應圖片
response.setContentType("image/jpeg");
int width = 150; //指定生成驗證碼圖片的寬度
int heigh = 60; //指定生成驗證碼圖片的高度
//獲得圖像數據緩衝對象
BufferedImage bi = new BufferedImage(width,heigh,BufferedImage.TYPE_INT_RGB);
//獲得圖形上下文的抽象基類
Graphics g = bi.getGraphics();
Random r = new Random();
Font f = new Font("黑體",Font.PLAIN,60); //定義字體樣式
g.setColor(getRandColor(200, 250)); //設置背景顏色
g.fillRect(0, 0, width, heigh); //繪製背景
g.setFont(f); //設置字體
g.setColor(getRandColor(180, 200)); //設置前景顏色
Graphics2D g2d = (Graphics2D) g;
//畫一條折線
//BasicStroke bs=new BasicStroke(5f,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL); //創建一個供畫筆選擇線條粗細的對象
//g2d.setStroke(bs); //改變線條的粗細
g2d.setColor(Color.DARK_GRAY); //設置當前顏色爲預定義顏色中的深灰色
int[] xPoints=new int[8];
int[] yPoints=new int[8];
for(int j=0;j<8;j++){
xPoints[j]=r.nextInt(width - 1);
yPoints[j]=r.nextInt(heigh - 1);
}
g2d.drawPolyline(xPoints, yPoints,8);
String sRand = "";
String ctmp = "";
int itmp = 0;
for (int i = 0; i < 6; i++) {
switch (r.nextInt(2)) {
case 1:
itmp = r.nextInt(26) + 65; // 生成A~Z的字母
ctmp = String.valueOf((char) itmp);
break;
default:
itmp = r.nextInt(10) + 48; // 生成0~9的數字
ctmp = String.valueOf((char) itmp);
break;
}
sRand += ctmp;
//設置每個字符的隨機顏色
Color color = new Color(20 + r.nextInt(210), 20 + r.nextInt(210), 20 + r.nextInt(210));
g2d.setColor(color);
//設置每個字符的隨機字體
g2d.setFont(this.getRandomFont());
//設置每個字符的隨機旋轉
AffineTransform at = new AffineTransform();
int number = r.nextInt(3)-1;
double role = number*r.nextDouble()*(Math.PI/4);
at.setToRotation(role,25*i+5,55-r.nextInt(20)); //role:旋轉角度,後面兩個參數是設置圍繞座標點旋轉
g2d.setTransform(at);
g2d.drawString(ctmp, 25*i+5,55-r.nextInt(20));
}
HttpSession session = request.getSession(true);
session.setMaxInactiveInterval(5*60);//設置session對象5分鐘失效
session.setAttribute("code", sRand.toString());
g2d.dispose();
System.out.println(sRand);
ImageIO.write(bi, "JPEG", response.getOutputStream());
}
public static Font getRandomFont() {
//String[] fonts = {"Georgia", "Verdana", "Arial", "Tahoma", "Time News Roman", "Courier New", "Arial Black", "Quantzite"};
String[] fonts = {"a_TrianglerCmUp","Astarisborn","WishfulWaves"};
Random r = new Random();
int fontIndex = r.nextInt(fonts.length);
return new Font(fonts[fontIndex], r.nextInt(3),50-r.nextInt(20));
}
}
<body>
<div><img src="checkcode" alt="驗證碼" id="check_image"/></div>
<a href="javascript:;" id="checkcode_a">看不清，換一張</a>
</body>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>驗證碼測試</title>
<script type="text/javascript" src="js/jquery-1.11.0.js"></script>
<script type="text/javascript">
$(document).ready(function(){
var i = 1;
$("#button").click(function(){
i = i+1;
var servletpath = "checkcode?a="+i;
var img = "<img src='" + servletpath + "' width='120' height='60'/>";
$("#image_div").html("");
$("#image_div").html(img);
});
});
</script>
</head>
<body>
<input type="button" id="button" value="showimage"/>
<div id="image">
sdfsdfsdfdsfsdf
</div>
<div id="image_div">
<img alt="" src="" id="image_code">
</div>
</body>
</html>